Direct estimation of functionals of density operators by local operations and classical communication
Carolina Moura Alves, Paweł Horodecki, Daniel K. L. Oi, L. C. Kwek, ARTUR K. EKERT · Physical Review A · 2003
We present a method of direct estimation of important properties of a shared bipartite quantum state, within the ``distant laboratories'' paradigm, using only local operations and classical communication. We apply this procedure to spectrum estimation of shared states, and locally implementable structural physical approximations to incompletely positive maps. This procedure can also be applied to the estimation of channel capacity and measures of entanglement.